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NIST Authors in Bold

Displaying 2551 - 2575 of 2915

Optical two-way time and frequency transfer over free space

April 28, 2013
Author(s)
Fabrizio R. Giorgetta, William C. Swann, Laura C. Sinclair, Esther Baumann, Ian R. Coddington, Nathan R. Newbury
The transfer of high-quality time-frequency signals between remote locations underpins many applications, including precision navigation and timing, clock-based geodesy, long-baseline interferometry, coherent radar arrays, tests of general relativity and

What Continuous Monitoring Really Means

July 24, 2012
Author(s)
Ronald S. Ross
[Print Title: "Establishing a Secure Framework"] Recently, NIST completed a fundamental transformation of the traditional certification and accreditation process into a comprehensive, near real-time, security life cycle process as part of a Risk Management

An Equation of State for the Thermodynamic Properties of Dimethyl Ether

June 6, 2011
Author(s)
Yong Zhou, Jiangtao Wu, Eric Lemmon
A thermodynamic property formulation for dimethyl ether has been developed based on a selection of experimental thermodynamic property data. The formulation includes a fundamental equation, a vapor pressure equation, and saturated density equations for

Rheological Characterization of Flow Table Reference Material

April 29, 2011
Author(s)
Chiara F. Ferraris, Haleh Azari
The flow table is a standardized test that is widely used to qualify a mortar to be tested for compressive strength and air content. It is also the only standard test to quantify a mortar workability property. Therefore, the calibration of this device is

When High-Quality Face Images Match Poorly

March 13, 2011
Author(s)
J. R. Beveridge, P. Jonathon Phillips, Geof H. Givens, Bruce A. Draper, Mohammad N. Teli, David Bolme
In face recognition, quality is typically thought of as a property of individual images, not image pairs. The implicit assumption is that high-quality images should be easy to match to each other, while low quality images should be hard to match. This

When High-Quality Face Images Match Poorly

March 9, 2011
Author(s)
J. R. Beveridge, P. Jonathon Phillips, Geof H. Givens, Bruce A. Draper, Mohammad N. Teli, David Bolme
In face recognition, quality is typically thought of as a property of individual images, not image pairs. The implicit assumption is that high-quality images should be easy to match to each other, while low quality images should be hard to match. This

Measuring Up to Sustainable Water: Report from the 2010 NIST/Virginia Tech. Water Workshop

September 9, 2010
Author(s)
Lauren F. Greenlee, Jessica D. Torrey, Stephanie A. Hooker, Michael J. Fasolka, Sunil K. Sinha, Marc A. Edwards
Securing water sources of sufficient quality and quantity poses a major barrier to growing communities. Major investments in capitol and materials are planned in water treatment and distribution system infrastructure over the next several decades, but

Study of Azeotropic Mixtures with the Advanced Distillation Curve Approach

April 11, 2009
Author(s)
Amelia Hadler, Lisa S. Ott, Thomas J. Bruno
Classical methods for the study of complex fluid phase behavior include static and dynamic equilibrium cells that usually require vapor and liquid recirculation. These are sophisticated, costly apparatus that require highly trained operators, usually

Improving Correlations with Inelastic Loss

June 6, 2008
Author(s)
James V. Porto
Correlations are one of the central features of modern condensed matter physics. They arise in systems where the behavior of any given particle in a system depends strongly on all the other particles. Such correlations are what help distinguish the

Reverse Engineering the Brain

November 9, 2007
Author(s)
James S. Albus
Reverse engineering the brain will require a deep understanding of how information is represented and how computation is performed in the brain. What are the functional operations? What are the knowledge data structures? How are messages encoded? How are

Voltage Instability in a Simulated Fuel Cell Stack Correlated to Cathode Water Accumulation

July 22, 2007
Author(s)
Jon P. Owejan, T Trabold, Jeffrey J. Gagliardo, Robert N. Carter, Daniel S. Hussey, David L. Jacobson, Muhammad D. Arif
Single fuel cells running independently are often used for fundamental studies of water transport. It is also necessary to assess the dynamic behavior of fuel cell stacks comprised of multiple cells arranged in series, thus providing many paths for flow of

On the Vickers Indentation Fracture Toughness Test

January 4, 2007
Author(s)
George D. Quinn, Richard Bradt
The Vickers indentation fracture toughness test or VIF is addressed by considering its origins and the numerous equations that have been applied along with the technique to estimate the fracture resistance, or the KIc of ceramics. Initiation and

Media Longevity Sidebar for INSIC

August 1, 2006
Author(s)
Oliver T. Slattery
The long-term preservation of digital data is a fundamental objective for many government agencies, businesses and individuals alike. With positive claims from manufacturers with regard to longevity, optical media has generated interest among the archival

Ab Initio Structure of the Active Site of Phosphotriesterase

February 1, 2001
Author(s)
Morris Krauss
This research exploits two recent developments to obtain a fundamental understanding of the metalloenzyme active site using the bi-metallic enzyme phosphotriesterase as an example of this class. First, is the theoretical prediction that the structure and

Treasure of the Past: II. The Atomic Weight of Bromine

July 1, 2000
Author(s)
Alan Weber
A considerable amount of work has been done in order to determine the atomic weight of bromine and the oft-repeated comparison of the atomic weights of silver and bromine makes it seem that this ratio is known with considerable accuracy. The value accepted

The Infrared Spectrum and Internal Rotation Barrier in HF--BF 3

May 1, 2000
Author(s)
K Nauta, R E. Miller, Gerald T. Fraser, Walter J. Lafferty
The rotationally resolved infrared spectrum of the HF stretch fundamental in combination with one quantum of internal rotationexcitation has been observed for the HF--BF 3 complex using a color-center-laser optothermal molecular-beam spectrometer.This

Watt's Up, Doc? The NIST Watt Experiment and the Future of the Kg

March 21, 2000
Author(s)
J. Schwarz, Ruimin Liu, David B. Newell, Richard L. Steiner, Edwin R. Williams
The Nist Watt Balance is an interesting and beautiful experiment housed in the nonmagnetic building behind the reactor. The underlying physical principles of the experiment are very simple: a current in a magnetic gradient will produce a force that is

Optimization of Polymer Concrete Composites: Final Report

August 1, 1999
Author(s)
L Czarnecki, A Garbacz, P Lukowski, J R. Clifton
The main aim of the study was the development of a method for the design and optimization of polymer concrete composites, using a fundamental approach based on a material model of polymer concrete. The polymer concrete materials were characterized via

Char Enhancing Approaches to Flame Retarding Polymers

February 1, 1998
Author(s)
Jeffrey W. Gilman, Takashi Kashiwagi, Richard H. Harris Jr., S M. Lomakin, J D. Lichtenhan, A. Bolf, P. Jones
Additives that increase the amount of charcoal-like residue or carbonaceous char that forms during polymer combustion are very effective fire retardants (FR). Our research efforts focus on reducing polymer flammability by promoting char formation. Our

Advances in NIST Standard Rockwell Diamond Indenters

January 1, 1998
Author(s)
Jun-Feng Song, Samuel R. Low III, David J. Pitchure, Theodore V. Vorburger
Recent developments in standard hardness machines and microform calibration techniques have made it possible to establish a worldwide unified Rockwell hardness scale with metrological traceability. This includes the establishments of the reference
Displaying 2551 - 2575 of 2915
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